messeges through ethernet

Hi all,

I am trying to send messeges via Ethernet from a couple PLC's to another. The receiving PLC is a Micro Logix 1100 and the PLC's sending the messege are a 1747-L552C 5/05 and a 1768-L43 Compact Logix5343 Controller. Has anyone done something like this yet and is it going to be a complication sending messeges from a compact logix to a micro logix? Any tips and help would be appreciated.

Thanks

Hi

What you are going to do will work so that is some good news.
I would always send a message from a compact logix to a 1100 as it easier that going from the 1100 to the compact

you will need the MSG instruction and I think it's the same in the slc.
They are set up a little different but are nearly the same.
There is a very good PDF on Ab.com about plc messaging and it well worth getting it.

I am only on my phone now so I don't have any code to show you.
But if you look at the help for MSG instruction it's very good


Donnchadh

messages through ethernet

Thanks for the reply. I am not having any issues with SLC to Micro. I just started sending a message from compact to Micro and getting an error code 16#0006. I think its the pathway is not set up correctly. Setting up the MSG file with the slick I had put in the IP address to the PLC I am wanting to communicate with and I am not able to do this on the Controls logic. Does anyone have some sample code that does not need control net?

Thanks

What you're looking for is the CIP Path in RSLogix 5000.

For a 1768-L43... I'll have to check my notes. Because there can be multiple network modules attached to a 1768-L4x controller, the Slot number isn't always 1, like it would be fore a CompactLogix 1769-L32E.

In general, the Path should be 1, 1, 2, [IP Address]

Where "1, 1" means "Backplane, then Slot 1"
and "2, IP Address" means "Out the Ethernet port to the IP address".

Knowledgebase article 43384 has examples but you must have a tech contract to view.

FWIW I always advocate using READ messages, because it gives you traceability. What I mean by this is if you had another machine writing data, a cross-reference will show no "source" for that data, being external. If that data was read, a cross-reference will show a MSG instruction, which you can look at to see where the data originates.

The only downside to this in your case is that you will have to use "PLC/SLC Mapping" in the CompactLogix, to recognise and deal with the PLC/SLC data-table style addressing, when a Read MSG comes in from a PLC/SLC/Micro

Just what I was looking for

Thanks guys that is just the info I am needing. I will try it out in the morning and let you know how it turns out.